Shortly after that, he said a fire alarm was sounded to alert personnel in the city’s offices at 165 Church St. to leave the building.

Grotheer said Church Street between Chapel and Elm streets was closed to traffic as fire and police responded to the threat at the two-story building where about half of the city’s public offices are located.

The spokesman said some workers headed home, while others waited across the street on the city Green.

About an hour and 15 minutes after the call was received, the street was reopened. No bomb was found.

The Board of Zoning Appeals meeting at 200 Orange St., which backs up to City Hall, was cancelled because of the threat and will be rescheduled.